import std.signals;
import std.stdio;
import std.conv;


class hh
{
     mixin Signal!();
     
    void haha(){emit();}
}


class ff
{
    void show()
    {
        writeln("ff show");
    }
}

void main()
{

    auto h = new hh();
    
    void show()
    {
        writeln("main show");
    }
    
    auto f = new ff();
    
    h.connect(&f.show); // It is ok to work
    //h.connect(&show); will erro.
    
    h.haha();
    
}
 
